T21 (December 12, 2006) Options

[Guest_AlexBlackwell_*]

The T21 Mission Description document is now online (1.2 Mb PDF).

[elakdawalla]

More SAR coming up!

Emily

[ugordan]

What's with this "XXX not available for Titan-21" stuff? Seems like less and less effort is put into these flyby descriptions, as it is now only a single page or so of new information is present per flyby. The rest is pretty much copy-paste stuff.
Also, as edstrick pointed out, it would have really been nice to also include science plans for the periapsis passes, at least listing what targets and instruments will be used.

[remcook]

it would have really been nice to also include science plans for the periapsis passes, at least listing what targets and instruments will be used.

The playback list was basically that, although it didn't say where exactly it is pointing at. But the name of some of the observations gave some hints. A shame it isn't available for this flyby, since it is one of the best north polar passes we have. I find it strange as well, since these tables already exist I imagine. It would just be a matter of copying them into the press release.

[volcanopele]

This is one of the few, decent trailing hemisphere passes of the mission for RADAR. It is a short pass, but should be good enough to understand the geometry of the dunes in northern Belet so we can compared those seen on T8.

In addition to Titan, be on the look for images of Pan (from around 750,000 km) and gibbous Dione from 300,000 km centered around 30 N, 135 W.

[Guest_AlexBlackwell_*]

This is one of the few, decent trailing hemisphere passes of the mission for RADAR. It is a short pass, but should be good enough to understand the geometry of the dunes in northern Belet so we can compared those seen on T8.

A good point, Jason. And I, too, am looking forward to this particular observation.

[alan]

Titan images are down. Some clouds visible:
http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=92452

[remcook]

some more clouds:

http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=92502

they also show up very nicely in the recent VIMS/Radar release.

[volcanopele]

These aren't in the VIMS/RADAR release. these images were taken yesterday.

[remcook]

I was talking about the mid-latitude clouds in more general terms. They are more pronounced in the VIMS/Radar release.

[tasp]

( my understanding of computer image processing is rather limited, so if this is really dum, or is already being done and I didn't notice, please be gentle )

For areas of Titan where we have both high resolution NA camera images and SAR data, could a mathematical correlation of the differences between the 2 data sets be generated, and then be applied to areas of Titan where we only have the NA camera data or only the SAR data to generate the other for both areas?

I think it isn't possible, but I am clueless as to why.

[Guest_Sunspot_*]

I assume the radar didn't reveal anything news worthy this time around?

[ugordan]

Whoa, hold your horses... Not even a week has passed after the flyby + it's weekend now. No point in rushing things!

[edstrick]

"For areas of Titan where we have both high resolution NA camera images and SAR data, could a mathematical correlation of the differences between the 2 data sets be generated, and then be applied to areas of Titan where we only have the NA camera data or only the SAR data to generate the other for both areas?"

That works when the two datasets are well correlated and can work nearly perfectly if one dataset can be mapped onto another dataset by a simple one-for-one function. It doesn't have to be linear or a simple curve or anything. You just need a unique Y value for each unique X value.

In multispectal data, we've done that with rover color images with datablocks missing. If a green data chunk is AWOL, a weighted average of the red and blue channels is a good visual match, but close inspection will show the only colors in the "fudged" part of an image are varying shades and intensities of orangy red through gray through greenish blue.. No yellows or greens, where the real data would be brighter than the average, no purples, where the real data would be darker than the average.

With something like VIMS and radar data, it's essentially impossible. Though you can match up features in the two datasets, actual data values have essentially no correlation and there's no possible "reasonally good" mapping from one dataset to the other. They are truely telling you two essentially independent, different things about the same surface.

An analogy is a red and green checkerboard. a 512 channel imaging spectrometer won't tell you anything more about the red and green squares than a single well selected channel. But pick thermal infrared or millimeter waves, and you might not see the checkerboard at all, but the fiber structure of the particle-board or masonite underneath the paint formnig the red and green squares.

[tasp]

I appreciate the response, that was very helpful.